Undercutter-guide.



S. S. SILVIS.

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' APPLICATION FILED MAY '9. 1913. 1 33131 1 n v Patented June 26,1917.

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S. S. SFLVIS.

UNDERCUTTER GUIDE. APPLICATION FILED MAY 19. I913.

1,231,21 1 o Patented June 26, 1917.

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ATTORNEY.

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SANKEY S. SILVIS, OF PORTLAND, OREGON. ASSIGNOR TO EDWARD LARKIN AND CHARLES LARKILKOF BLIND SLOUGH, OREGON.

UNDERCUTTER-GUIDE.

Application filed May 19, 1913.

To alt whom it may concern:

Be it known that I, SANKEY S. SILVIS, a citizen of the United States, residing at Portland, in the county of Multnomah and State of Oregon, have invented new and useful Improvements in Undercutter-Guides, of which the following is a specification.

This invention relates to devices used in cutting timber, and has particular reference to improved means for guiding the saw used in such instances.

After a log is on the ground it is cut up to predetermined lengths, and this operation is performed by sawing into the log both from the top and bottom in order to prevent the log from splitting. It is customary, in thus sawing into a log from the bottom, or undercutting as it is usually termed, to support and guide the saw in order to facilitate this operation.

The object of this invention is to provide a support and guide of improved construction. A further object is the provision of means whereby the guide may have a wide range of adjustment so as to be-readily applicable to any size of log. Finally I aim to introduce, in a device of this character, the various advantageous features hereinafter clearly set forth, and drawings are hereunto appended in which the objects and features of the invention are fully illustrated. In the drawings:

Figure 1 is a side elevation showing the device attached to a log, as in practice,

Fig. 2 is an end-elevation of the device,

Fig. 3 is a plan view partly in section,

Fig. 4: is a cross sectional view through the center of the device, and

Fig. 5 illustrates, in cross section, the guide roller.

Referring in the first instance to Fig. 1, the device isshown attached to the log 1, and the saw is shown in operative position. The said log and saw, not forming part of the invention, are merely indicated in dotted outline.

The device comprises a body-portion having a bifurcated head 4 and provided with a striking surface 5. The shank 3 of said body-portion is preferably made square and may conveniently at its outer end he threaded or otherwise adapted to receive a stopcollar 6.

The second member of the device is a guide roller 7 having a plurality of p'eriph Specification of Letters Patent.

Patented June 26, 1917.

Serial No. 768,684.

eral grooves in any one of which the back of the saw is free to ride. The guide-roller T is rotatably fixed on an arm 8, and the latter is connected to the shank 3 through the medium of a clamping device 9.

Said clamping device consists of a stud 10 having a transverse perforation shaped and proportioned to fit the shank 8, so that the stud is free to slide smoothly back and forth on said shank. At one end of the stud is provided a head, inwardly tapering, and the opposite end of the stud is threaded to receive a clamping lever 11. A collar 12 is loosely hung on the stud intermediate said lever 11 and the shank 3, and said collar is conveniently made with a shoulder-portion 13 for engagement with a corresponding shoulder of the stud. Thus the collar is held from moving across the perforation of the stud, and the mounting of the stud on the shank thereby greatly facilitated.

A-cylindrical sleeve 14 is made with a con centric perforation having a tapered shoulder on which the tapered head of the stud is fitted to ride. In order to assemble the parts the'stud is first pushed through the perforation of the said sleeve 14 until the said shoulders engage each other, the collar 12 is next mounted-and the clamping lever 11 applied. The stud is mounted on the shank 3 of the body-portion of the device, and the clamping lever is then turned until the opposed faces 15, 16 of. the collar 12 and the sleeve 14 engage the sides of the shank, thereby locking the parts firmly in place. The said collar 12 is furthermore conveniently made with a recessed portion 17. which rides on the shank in order to keep the collar from rotating when the clamping lever 11 is turned.

The sleeve 14 has a cylindrical bore, transversely directed and proportioned to slidably fit the arm 8 of the guide-roller 7. A collar 18 is slidably fitted on the outer pcriphery of said sleeve, and this collar is on one side provided with two transverse grooves 19, 20, said grooves disposed at right angles toeach other. It is noticed that the groove 19 is circular and that the groove 20 has a straight bottom. The guide-arm .8 has a flattened portion 21. Now, when the collar 18 is turned so that the flattened groove 20 registers with the perforation of the sleeve 14, and the guidearm is inserted, as best shown in Fig. 8, then the said arm;

is locked in said groove against turning, whereas, when the collar is placed, as shown in Fig. 4;, with the circular groove 19 in registration, then the said arm may be ad justed circumferentially.

The lower end of the shank 3 is made cylindrical, and the diameter of this cylindrical portion equals the width of the side of the square portion. By this construction the clam aing device 9 may conveniently be moved on to said cylindrical portion and given a quarter turn or a half turn on the shank, whereupon it is again caused to slide on to the square portion of the shank and clamped in place. The guide-roller may thus be set at various angles to the shank without taking the entire device apart, and the stop-collar 6 prevents the clamping de: vice from slipping off the shank.

It has been found in practice that the guide-roller ofa device of this character quickly runs dry and cuts into its bearing, It thus does not revolve freely, and the saw wears deep grooves in its periphery. In order to overcome this diflicnlty the guideroller is conveniently constructed and mounted as best shown in Fig. 5. The guidearm 8 is made with a cylindrical heel 23 on which are detachably fixed pair of shouldered sleeves 24:, 25 in spaced relation. The roller 7 is bored to revolve on the outer periphery of said sleeves, and it is held against longitudinal displacement between the shoulders of said sleeves. A cylindrical chamber is thus formed within the roller, and this chamber is filled with suitable lubricants, which will keep the bearing in condition for a long time. The sleeve 25 conveniently locked in position-by a cotter-pin 26, and this pin is readily withdrawn and the said sleeve removed, when it is desired to clean the bearing and to replenish the supply of lubricants.

From the foregoing description it is seen that an undercutter guide of wide adjustment is provided, inasmuch as both the body-portion and the guide-arm are adjustable lengthwise and circumferentially. The device can also be folded very close to the log so as to retain the benefit of the full length of the saw, and so that the device, when the log parts, is in no danger of being bent or otherwise damaged.

It is stated above that the guide-arm 8 has flattened portion 21, but it is obvious that more than one flattened surface may be provided so as to lock the arm in different relations. The tapering portion of the stud 10 and the corresponding tapering portion of the sleeve l-l may conveniently be made with milled or otherwise roughened surfaces in order to assist in locking said parts against relative rotation.

I claim:

1. In an under-cutter guide, an elongated body, arm having a flattened side surface, and a clamping joint including a sleeve having a transverse bore and a collar loosely hung on said sleeve, said collar having a circular groove and a flat bottom groove for registration with said bore, the devices being so related that the said arm, through the medium of said grooved collar, is mountable in the bore of said sleeve for angular adjustment or angularly fixed according to the positioning of the said collar.

2. An undercutter guide comprising in combination ashank having a head for attaching it to a log, a guide arm carrying a grooved roller, a stud having a transverse perforation in which said shank is slidably mounted and provided with screw threads on its outer end, a sleeve surrounding one end of said stud, in which said stud is seated and with relation to which the stud is rota table, said sleeve being transversely perforated by a circular bore to receive said guide arm, said guide arm being of generally circular outline to correspond with said bore but havingaiiattened face a collar on said sleeve intermediate said shank and said arm one edge of which is designed to engage said guide arm, said edge of said collar having two grooves therein for registration with said bore, said grooves being arranged to cross each other one being semi-circular and the other having a flat bottom for engagement with the flattened face of said guide In testimony whereof I have hereunto affixed my signature.

SANKEY s, sILv s. In presence of G, BLAINE. NissEN, DAVID E, LOFGREN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

